Volcanic is a primary biome type characterized by intensely hot temperature with hard scorched Magmarock, ash and scattered pools of lava. Volcanic planets are an 'inconceivable' threat level, geared toward tier 6 in progression. It is similar in appearance and temperature to Magma planets, but doesn't have oceans of lava. Glitch settlements have a higher chance to appear on volcanic planets.

Volcanic (Terraformed) biomes can be created and expanded using a Volcanic Terraformer, and a planet will convert to a Volcanic planet once half of the planet's surface has been terraformed into Volcanic (Terraformed) biome. The terraformed version of the Volcanic biome is like the normal version apart from the lack of the Deadly Heat status effect (this allows you to use a backpack other than a Cooling EPP without causing you to burn to death).

Volcanic planets can only be found orbiting fiery (red) star types. Unless players have a Cooling EPP Upgrade equipped they'll take increasing damage while on the surface from deadly heat.

Possible mini biomes inside volcanic biomes are foundry, which has workers slaving away over hot lava forges, geode, desingished by its glowing crystals, and bones with piles of dry bones scattered in piles.

Sub Biomes

There are sub biomes which can be found on volcanic planets in addition to their unique mini biomes. Midnight, desert, decayed, or forest have a chance to appear as smaller biomes on volcanic planets. These biomes will include things like their associated blocks, trees, and crops when they appear. Mini biomes for each of these secondary biome types can appear inside them as well.

Mini Biomes

Foundry, geode, and bones are mini biomes found inside volcanic biomes. These mini biomes can be found on volcanic planets or inside volcanic sub biomes on other planet types. These mini biomes each have their own creatures and items outside what's available in volcanic biomes.

Weather on volcanic planets is either clear with a chance of cinder showers or light ashfall, or clear with a chance of cinder showers, in addition to small or large meteorites. Each magma planet has one of these two pools of weather, and it will not change. Magma planets without a meteorite shower chance will never have meteor shower weather and cinder shower weather has a chance to appear on all volcanic planets. Cinder weather will burn and destroy structures made with wood material.

Weather happens for each planet based on the weights given to the weather types (probability is calculated by dividing a single weight by the sum of all weights); the probability for weather types on volcanic planets is as follows:

Wildlife

In addition to procedurally generated creatures, there are a variety of unique monsters, bugs and critters found in volcanic biomes. Some of these are also found in other biomes, while others are unique only to volcanic biomes. While these unique creatures have a chance to appear on volcanic planets, they will not all appear on each one. In addition to unique creatures, each biome has multiple types of both procedural ground and flying creatures.

Unique monsters each have combat attacks, and they must first be weakened before capture. Once weakened players can attempt to capture using a capture pod. If successful they can then be released to battle alongside and follow the player.

Critters are smaller non-combat unique creatures which are not capturable using capture pods. They can be captured without weakening them first by using a relocator gun. After releasing a critter from the relocator it will stay in the area it was released into.

Bugs are very small unique creatures which can be captured using a bug net, and are then stored inside placeable jars. Bugs which are captured using a relocator will fly after release instead of being kept inside a jar.

Unique Drops

There are a variety of items which are specific to chests found in volcanic biomes. Some of these may have a chance of being found in other places throughout the universe, but they've all been specifically allocated to chests within volcanic biomes.

Volcanic Chest is related to this biome, and has a number of unique drops allocated to it.

Settlements

Decayed biomes have a chance to have most settlement types appear. Glitch dungeons and settlements are the most likely type to be found on volcanic planets, and it's the planet type where their settlements are most likely found.